In a spring-actuated stapler, a striking plate is reciprocally movable between an initial position and a fire position. When the striking plate moves from the initial position to the fire position, an actuation striker spring, which is engaged with a hole on the striking plate, is deformed and energized. When the striking plate reaches the fire position, the striker spring is released to resume its initial shape, in the process driving the striking plate to its initial position to dispense to a work piece a leading staple of a stable stick contained in a staple magazine. A triggering lever is provided to engage with a hole on the striking plate so as to pull the striking plate from the initial position to the fire position when a force is applied on a cover plate during a stapling operation, and then disengages from the hole to release the striking plate to be driven back by the energized striker spring.
In prior systems, a biasing return spring mechanism is also provided to bias the triggering lever back to its initial position in which the triggering lever engages with the hole of the striking plate. Conventionally, the triggering lever is located between the cover plate and the staple magazine (or the body that comprises the magazine), which makes the design of the stapler complicated with more components.